配置hibernate有关问题

<session-factory>        <!--配置数据库连接 -->        <property name="connection.url">            jdbc:oracle:thin:@localhost:1521:orcl        </property>        <property name="connection.username">scott</property>        <property name="connection.password">tigger</property>        <property name="connection.driver_class">            oracle.jdbc.driver.OracleDriver        </property>        <property name="dialect">org.hibernate.dialect.Oracle10gDialect</property>        <!-- 是否打印Sql语句 -->        <property name="hibernate.show_sql">true</property>        <mapping resource="com/szy/hibernate/user.hbm.xml" />    </session-factory>

<hibernate-mapping package="com.szy.hibernate"> <class name="User" table="t_user">  <id column="ID" name="id" length="10" type="java.lang.String">   <generator class="assigned"/>  </id>  <property column="USERNAME" name="username" type="java.lang.String" length="20" not-null="true" unique="true"/>  <property column="PASSWORD" name="password" type="java.lang.String" length="20"/>  <property column="AGE" generated="never" lazy="false" name="age" type="java.lang.Integer"/> </class></hibernate-mapping>

Configuration config=new Configuration().configure();        SchemaExport export=new SchemaExport(config);        export.create(true, true);

User user=new User();        user.setId("001");        user.setUsername("coolszy");        user.setPassword("test");        user.setAge(21);                Session session=HibernateUtil.getSession();        Transaction ts=session.beginTransaction();        session.save(user);        ts.commit();